Electrical assembly



March 5, 1957 w, c, MaGFADDEN 2,784,386

ELECTRICAL ASSEMBLY Filed May 26, 1953 'waIilIIlvl km IN VENTORZ WILF'ORD 6. MM F'ADDEN,

BY m/Zm ATTORNEY.

United States Patent ELECTRICAL ASSEMBLY Wilford C. MacFadden, Fox Chase, Pa., assignor, by

m'esne assignments, to United-Carr Fastener Corporation, Boston, Mass., a corporation of Delaware Application May 26, 1953, Serial No. 357,419 3 Claims. (Cl. 339128) This invention relates generally to connectors and has particular reference to a snap-in connector for use in high-voltage electrical apparatus.

In the construction of television receivers, an electrical connection must be made to the conductive coating on the inside of the kinescope tube. This is ordinarily accomplished by providing a connector embedded in the glass of the tube so that it makes electrical contact with the inside coating, and has an exterior socket to receive a snap-in connector.

Certain types of kinescope tubes now in production require up to 30,000 volts for satisfactory operation, compared to about 8,000 volts maximum in the older tubes. It has been found that connectors satisfactory for use with the lower voltage tubes are not suitable for use with the higher voltage tubes because of the excessive amount of corona produced at the connector by the high voltage.

Although a small amount of corona is produced by the voltages used in the older type of tube, this has been easily controlled by providing a rubber shield over the connector. However, the higher voltages now used produce sufiicient corona to cause rapid deterioration of the rubber shield, even when special types of corona resistant rubber are used.

The object of this invention is to provide a connector for high-voltage apparatus which is so constructed as to eliminate entirely corona resulting from high voltage applied to the connector.

A further object of the invention is to provide a connector for high-voltage apparatus which has no portion subject to deterioration by reason of corona resulting from high voltages applied to the connector.

Another object of the invention is to provide a connector for attaching a lead wire to a kinescope tube, in which means is provided surrounding the lead wire and connector for preventing corona which otherwise would be developed by high voltages applied to the connector.

Other objects of the invention will, in part, be obvious and will, in part, appear hereinafter.

In the drawing:

Fig. 1 is an exploded perspective view of a connector embodying the features of the invention;

Fig. 2 is a view in section of the connector of Fig. 1 assembled into a cooperating fastener in a kinescope tube; and

Fig. 3 is an end view of the assembly of Fig. 1.

Referring to the drawing, there is illustrated a connector assembly 10, which is adapted to receive a lead Wire 12 and snap into engagement with a connector socket 14 disposed in the wall of a kinescope tube 16.

The tube 16, in the illustrated embodiment, comprises a glass wall 18, having an interior conductive coating 20. To provide means for making external contact with the coating 20, the connector socket 14 is embedded in the wall so as to be in electrical contact with the coating and provides an outwardly facing contact portion comprising a plate 22 having an opening 24.

2,784,386 Patented Mar. 5, 1957 The connector assembly 10 comprises a base 26 having a series of shouldered spring arms 28 extending therefrom, and a corona shield 30 assembled onto the base by means of a hollow eyelet 32, which is adapted to receive the lead wire 12, which may be retained therein by solden'ng or the like.

The corona shield 30 comprises a hollow cup-shaped body preferably formed of sheet metal, having a base portion 34 seated on the connector base 26 and an upstanding peripheral wall 36 disposed about the base. The Wall 36 is preferably outwardly rounded, and the upper edge of the wall is curled inwardly and downwardly to terminate in an edge 38 disposed within the wall 36. The wall 36 is preferably outwardly rounded, and the upper edge of the wall is curled inwardly and downwardly to terminate in an edge 38 disposed within the wall 36. The dimensions of the shield 30 are such that the wall 36 peripherally encloses the junction of the lead wire 12 with the eyelet 32 in radial spaced relation thereto, and the edge 38 also is disposed about the wire in radial spaced relation an appreciable distance longitudinally of the wire from the junction with the eyelet. In the preferred embodiment, the base portion 34 of the shield is provided with a medial recessed portion 40 to receive the base 26 of the connector, to securely align the shield on the connector and to at least partially embed the connector.

The connector assembly 10 is readily assembled into the socket 14 in the tube by snapping the shouldered legs 28 into the opening 24 where it is securely retained by the spring action of the legs.

One characteristic of corona is that it occurs only at sharp edges or corners. In the illustrated corona shield, the sharp edge is disposed within the smooth exterior portions. Since all portions of the shield are at the same potential, no corona can be produced at the edge disposed inside the shield. Since the design of the shield enables it to be formed of metal, the corona causes no deterioration of the shield.

The external shape of the shield is not critical, so long as it provides a smooth external surface with no external sharp edges or corners.

Since certain obvious changes may be made in the device without departing from the scope of the invention, it is intended that all matter contained herein be interpreted in an illustrative and not in a limiting sense.

I claim:

1. A connector, comprising a base having a series of shouldered spring fingers extending from one side thereof for snapping engagement into a cooperating connector, means medially disposed on the base for receiving a lead wire, and a metallic corona shield disposed on the base, said shield having a lower portion superimposed on the base with a small opening to receive the lead wire, a peripheral wall disposed on said lower portion and extending from the base in a direction generally opposite to that of the spring fingers and surrounding the means for receiving the lead wire in radial spaced relation there to, the upper end of said wall being curled inwardly and downwardly to terminate in an edge disposed within the upwardly extending portion of the wall.

2. A connector, comprising a connector portion having a base, a medial opening in the base and a series of shouldered spring arms extending from one side of the base for snapping engagement into a cooperating connector socket, a metallic corona shield assembled onto the other side of the base, said corona shield having a lower portion seated against the base, said lower portion having a medial opening, a hollow eyelet extending through the opening in the lower portion of the corona shield and the base retaining said shield in assembly on the base, said eyelet being adapted to receive the end of a lead wire therein, said corona shield having a peripheral wall disposed on the lower portion and extending therefrom in a direction generally opposite to that of the spring arms forming a hollow body for surrounding the lead wire With the eyelet in radial spaced relation, the upper end of said wall being curled inwardly and downwardly to be disposed inside the peripheral wall.

3. A connector comprising a base portion having connector means extending from one side thereof for engagement into aconnector socket, means on the base for receiving a lead wire, and a metallic corona shield associated with the base, said corona shield comprising a cupshaped member having a continuous Wall extending outwardly from the base in a direction generally opposite to that of the connector means and terminating in a continuous edge which is curled inwardly and downwardly into the interior of the cup-shaped member.

References Cited in the file of this patent UNITED STATES PATENTS 1,962,326 Randall June 12, 1934 2,000,673 Terman May 7, 1935 2,323,148 McLaughlin June 29, 1943 2,448,808 Koch Sept. 7, 1948 2,626,978 Coyle Jan. 27, 1953 FOREIGN PATENTS 558,199 Great Britain Dec. 24, 1943 

